Jet turbine bucket wheel



R. G. FRANK JET TURBINE BUCKET WHEEL Filed Oct. 24, 1958 FIG 5 FIG. 9

INVENTOR. ROBERT G. FRANK M/u. Ma

7 FIG. 0

A TTO ENE 75 3,032,317 JET TURBHNE BUQKET WHEEL Robert G. Frank,Cincinna @hio, assignor to the United States of America as representedby the Secretary of 3,032,3l7 Patented May 1, 1962 FIG. 3 is a viewsimilar to FIG. 1 but showing additional means for supplying air to theairfoil body of the bucket;

FIG. 4 is a view similar to FIG. 1 but showing a diftion;

FIG. 2 is a view similar to FIG. 1 but showing a different type of wheelstructure;

the Fame 5 terent type of turbine wheel;

Filed Oct. 24, 1958, Ser. No. 759,524 FIG. 5 is a fragmentary sectionalview showing a thin I Ciaim. (Cl. 253-47) solid Wheel;

FIG. 6 is a transverse sectional view of any of the tur- The presentinvention relates generally to buckets for bine buckets shown in FIGS. 1to 5, inclusive; use in jet turbines and as illustrated herein relatesmore FIG. 7 is a view, in section, showing th wires u et particularly toturbine buckets of the type wherein air is and b d t th h b f .tharrangements Shown i circulated through the bucket for reducing thetempera- FIGS. 1, 2 and 3; ture thereof. FIG. 8 is a view, in section,showing a modification of l engines and the like, an axial flow turbineP- the wheel shown in FIG. 3 wherein the bucket wires are erated byexhaust gases is usually provided which drives upset d b d to h inner ia blower for furnishing air under pressure to the burners. FIG, 9 is aview, in section, showing the bucket wires These turbines operate atvery high temperatures and it upset d b d to h outer i d is desirable toprovide suitable means for reducing the FIG, 10 i a fra me ta ysectional i Showing the temperature a Point Where damage to turbinePaYts is bucket wires upset and brazed to the rim of the wheel reducedsubstantially. Shawn i F G, 4,

It hefetefofe, been P p to form aXial how The drawings show turbinewheel designs of diiferent turbine buckets With radial Passages thePassage of types. The wheels shown in FIGS. 1, 2 and 3 disclose asuitable cooling fltlid- Such hllekets, however, have the bucket formingwires attached to the hubs of the been expensive, heavy and difiicult tomanufacture. One h l d i G 4 5, 7 9 and 10 the bucket fo object of thepresent invention is to provide an inexpensive i Wires are attached tothe rim of the Wheel. bucket which is relatively light and easilymanufactured. h design shown in HQ 1 shows the bucket f r i T s end andin accordance with one feature, the wires 10, attached to the hub 12 byupsetting and brazing invention contemplates new and imPIOVed turbinebuckets the ends of the wires it} after they have been inserted inwherein high temperature, high strength 3 Wire such holes formed in thehub 12. Spacer rings 14 are brazed as molybdenum could be attached as anintegral part to to the wires f rigidity and as a heat Seal at the plateither the hub or the rim of a turbine wheel in any suitform, AS Shown iFIG 2 a h d 13 may he brazed able manner. Sheaths formed from oxidationresistant to the i f the buckets m fo thg purpose of maintainmaterialare attached to the Wires to form the airfoil surihg the Shape th ofThin Solid disks 1 are Welded f The g Weight of this ConstructionPermits the to the hub 12 and spacer rings 14 for torque conversion. useof a substantially lighter wheel. As illustrated, the Thg hub 12 and theSpacer rings 1 are Suitably mhigh temperature, high strength alloy wiresmay be serated to permit i li cured to either the rim or the hub of theturbine wheel Th wires 10 are formed of high temperature, high insertingthe ends 0f the Wires through Openings, P- strength alloy. The wire andother parts of the turbine setting the ends of the Wire and then brazingthe Upset structure may be fabricated from molybdenum or plated ends tothe Wheel- This Provides not y an effective with an oxidation resistantmaterial. Other high temmethod of anchoring the blades to the Wheel butproperature high strength alloys may he used, Wires 10 vides also ablade which is hollow and thus may readily preferably are formed frommolybdenum or a molybbe cooled. This enables the elimination of many ofthe denum alloy which is sufficiently ductile to be drawn. problemsassocited with separate turbine components and Sheet metal and othershaped, cast or molded parts may permits operation at exhaust gastemperatures as high be formed from other suitable alloys. as 2600 F,Suitable alloys include the following:

Carbon Manganese Silicon Chromium Nickel Cobalt Molyb- Tung- Colum- (O)(1 11 (Si) (Cr) (Ni) (Co) denum sten bium (M0) (W) 0.26 0.52 0.57 18.959.05 1.22 1.10 0. 29 0.11 0.60 0.42 18.87 8.63 0.40 1.36 0. 28 0.15 0.600.70 15.0 30.0 Timken:

16-25-6 0.08 1.35 0.69 16.72 25. 23 6.26 S495 0.41 0.68 0.34 13.92 19.714.28 N-155 0.14 1. 48 0.52 21.3 20.0 20.0 3.06 N-155- 0.32 1.54 0.5921.08 20.80 20.54 3.0 S8l6 0. 30 0.72 0.19 18. 40 20. 23 45.63 4. 23HastelloyB 0.05 0.59 0.19 65.1 28.63 Haynes (cast) Stellite No. 2L. 0.2027. 51 Balance 5.63 Haynes Stellite No.30 422-19) 0. 40 0. 30 0. 5124.75 15.92 Balance 6.08 Haynes Ste1liteNo.31(X-40)- 0.48 0. 64 0. 7225.12 9. 69 55.23

With the above and other objects and features in view It is to be notedthat the wire receiving openings are the invention will now be describedwith particular refarranged to form an airfoil surface of a type usualin erence to the accompanying drawings in which; turbine buckets for jetengines. The airfoil section of a FIG. 1 is a schematic View, partly insection, of a turturbine bucket 25 depicted in FIG. 6, shows clearly thebine bucket constructed according to the present invenspacing andpositioning of the wires 10. It is evident that 70 closely spaced wires10 form a relatively stiif shape about which a sheath 22 is wrapped. Theinner surface of the sheath 2?. and the wires 10 are coated with asuitable brazing alloy and, after assembly, the sheath 22 and the wires10 are welded together by any usual method. The outer surface of sheet22 may be coated with an erosion and corrosion resistant material.

The construction shown in FIG. 3 is similar to that shown in FIG. 1except that the sheath 22 of the bucket 20 shown in FIG. 3 extends downto the inner rings 14. In this construction the sheath 22 between therings 14 could be formed of a lower temperature alloy material since itis not directly subjected to high temperatures to which the outer endportion of the sheath is subjected.

The wheel shown in FIG. 4 comprises a wheel fabricated from highstrength alloy wire forming spokes 23 similar to a bicycle wheel fixedto the hub 12 and to the outer rim 30. The spokes 28 are covered bydisks 32 which are also suitably fixed to the hub 12 and an inner ring34.

The construction shown in FIG. 5 illustrates a solid forged wheel 38 onwhich are mounted turbine buckets similar to the ones shown in FIG. 4and FIG. 10.

In FIGS. 7 to 10, inclusive, are disclosed various types of blade basesor supports to which the wires are secured. The construction shown inFIG. 7 is substantially the same as the embodiment shown in FIG. 1wherein the wires 10 are secured to the hub 12. FIG. 8 shows aconstruction similar to that shown in FIG. 2, but wherein the wires 10are secured to the inner ring 114 instead of to the hub 12. Theconstruction shown in FIG. 9 is similar to that shown in FIG. 8 exceptthat the ends of the wires 10 are secured to the outer ring 14. The FIG.10 construction is substantially identical to that shown in FIG. 4wherein the wires 10 are secured directly to the rim 39.

Regardless of how the wires 11) are secured to the blade base orsupporting structure the procedure followed in forming the sheath 24}about the blade is substantially the same. Brazing alloy may be applieddirectly to the wires by dipping, flame spraying or other suitable meansas hereinbefore stated.

Having thus described my invention, what I claim as new and desire tosecure by Letters Patent of the United States is:

A turbine bucket arrangement for jet engines comprising a bucket ofairfoil cross section and a support References Cited in the file of thispatent UNITED STATES PATENTS 2,189,785 Fahrney Feb. 13, 1940 2,369,795Planiol Feb. 20, 1945 2,780,435 Jackson Feb. 5, 1957 2,783,967 ScharfMar. 5, 1957 2,866,618 Jackson Dec. 30, 1958,

FOREIGN PATENTS 235,304 Great Britain June 12, 1925 715,421 Germany Dec.20, 1941 722.341 Great Britain Jan. 26. 1955

